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http://dx.doi.org/10.4334/JKCI.2002.14.5.689

Dynamic Fracture Behaviors of Concrete Three-Point Bend Specimens  

연정흠 (인하대학교 토목공학과)
Publication Information
Journal of the Korea Concrete Institute / v.14, no.5, 2002 , pp. 689-697 More about this Journal
Abstract
The dynamic loads and load-point displacements of concrete three-point bend (TPB) specimens had been measured. The average crack velocities measured with strain gages were 0.16 ㎜/sec ∼ 66 m/sec. The fracture energy for crack extension was determined from the difference of the kinetic energy for the load-point velocity and the strain energy without permanent deformation from the measure external work. For all crack velocities, there were micro-cracking for 23 ㎜ crack extension, stable cracking for 61 ㎜ crack extension at the maximum strain energy, and then unstable cracking. The unstable crack extension was arrested at 80 ㎜ crack extension except the tests of 66 m/sec crack velocity. The tests less than 13 ㎜/sec crack velocity and faster than 1.9 m/sec showed static and dynamic fracture behaviors, respectively. In spite of much difference of the load and load-point displacement relations for the crack velocities, the crack velocities of dynamic tests did not affect on fracture energy rate during the stable crack extension due to the reciprocal action of kinetic force, crack extension and strain energy. During stable crack extension, the maximum fracture resistances of the dynamic tests was 147％ larger than that of the static tests.
Keywords
concrete; TPB specimen; fracture behavior; crack velocity; fracture resistance;
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  • Reference
1 Jenq, H. K. and S. P. Shah, "A Two Parameter Fracture Model for Concrete," Journal of Engineering Mechanics, ASCE, Vol. 111, No. 4, 1985, pp.1227 -1241.   DOI   ScienceOn
2 Yon, J. H., Hawkins, N. M. and Kobayashi, A. S., "Numerical Simulation of Mode I Dynamic Fracture of Concrete," Journal of Engineering Mechanics, ASCE, Vol. 117, No. 7, 1991, pp.1595-1610.   DOI
3 Yon, J. H., Hawkins, N. M. and Kobayashi, A. S., "Comparisons of Concrete Fracture Models," Journal of Engineering Mechanics, ASCE, Vol.123, No. 3, 1997, pp.196-203.   DOI   ScienceOn
4 연정흠, "콘크리트 삼점휨 시험편의 성장하는 균열에 대한 저항곡선," 한국콘크리트학회 논문집, 제13권, 6호, 2001, pp.568-574.   과학기술학회마을
5 Mindess, S. and Shah, S. P., "Cement.. Based Composites: Strain Rate Effects on Fracture," Materials Research Society, Pittsburgh, Pennsylvania, 1985, p.270.
6 Clough, R. W., "Dynamics of Structures," McGraw Hill, New York, 1975, p.634.
7 Krstulovic-Opara, N., "Fracture Process Zone Presence and Behavior in Mortar Specimens." Materials Journal, ACl, Vol. 90, No. 6, 1993, pp.618-626.
8 Hillerborg, A., Modeer, M. and Petersson, P. E., "Analysis of Crack Formation and Crack Growth in Concrete by Means of Fracture Mechanics and Finite Elements," Cement and Concrete Research, Vol. 6, No. 6, 1983, pp.345-356.   DOI   ScienceOn
9 Li, Z. "Microcrack Characterization in Concrete under Uniaxial Tension." Magazine of Concrete Research, Vol. 48, No. 176, 1996, pp.219-228.   DOI   ScienceOn